Clapper box and block



Nov. 29, 1949 M, WALTER 2,489,942

CLAPPER BOX AND BLOCK Filed March 8., 1946 llll D In:

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' ATTORNEYS.

Patented Nov. 29,1949

CLAPPER BOX AND BLOCK John M. Walter, Cincinnati, Ohio, assignor to TheG. A. Gray Company, Cincinnati, Ohio, .a.c0r-

poration of Ohio Application March 8, 194.6, Serial "No. 653,223

In metal planers, the cutting tool is clamped securely to a hingedblock, known as a clapper block, which is in turn hinged to a clapperbox. The tool is so held-that upon movement of the Work in one directionbeneath the block, the tool will cut the work, and the hinging of theblock issuch that on the return stroke of the work, the block will swingon its pivot permitting the tool to drag readily on the work. Moremodern planers utilize a device which positively lifts the block andholds it in position so that the tool is out of contact with the workduring thereturn stroke.

The wear which takes place in this tool mounting structure in metalplaners is on the pivot for the block. When the pivot pin wears theblock will become loose and there will be a tendency of the tool tochatter, which results in a poor quality of work.

The object of the present invention is to greatly minimize thepossibilities of wear on the clapper block pivots by a structure ofblock and clapper box whereby the load of the cutting force is taken byfixed abutments and not by the pivots for the block.

It is old in the art to undercut the bottom edge of the clapper box andprovide for a projection on the clapper block which swings under theshoulder formed by the undercut. This takes the upward thrust on theclapper block. It is also old to provide for an upward thrust takingabutment at the top edge of the clapper block, but in such instances asI have been able to examine, which employed this type of device, thethrust had a tendency to apply a resultant thrust against the blocksupporting pivots. There has been no arrangement, to my knowledge, inwhich the cutting forces acting lengthwise of the tool and also thoseforces crosswise of the tool were taken up otherwise than by the pivotpin. Particularly where the tool is extended a considerable distancebelow the clapper block, there is a strong load applied by a leverageaction tending to force the pivots of the clapper block outwardly awayfrom the box.

In the drawings, I have illustrated a preferred construction embodyingmy inventions and in the claims that follow I will set forth the noveltyinherent in this example and other equivalent structures.

In the drawings Fig. 1 is a front elevation of a clapper box and. blockemploying my novel features. Fig. 2 is a section on the line 2-2 of Fig.1.

, In the illustrated form, the clapper box I has lateral ribs 2-2between which the clapper block 5. is located. A pivotshaft or pin 3 ismounted in bosses 4 at the upper edges of the ribs 2, for mounting theclapperblock.

The clapper block 5with its tool mounting posts it, is mounted over thepivot pin, as shown, and swingsupon it as a pivot.

The lower edge of the clapper box is undercu as at l forming'a shoulderand the lower edge of the clapper block is provided with a heavy lug orrib '8 which swings under thisshould er and takes abutment against itwhen the block is' in operating position (the position shown in Fig. 2)The abutments are at right angles being 1-8 (vertically) and la-Ba(horizontally).

The body of the clapper box above the channel in which the block islocated, has developed thereon a projection 9 which has an overhanginglip ID, that serves as a clapper block adjustment. To this end the upperedge of the clapper block is provided with a reduced portion resultingin a vertical abutment l which when the block is in operating positionabuts against the lip I0. In order to permit of swinging of the clapperblock,

r the box is recessed beneath the projection 9 as indicated at l2, thusclearing the abutment II and permitting the block to swing withreference to the box.

As an extra precaution, it has been found desirable to provide anabutment face I 3 on the clapper 'box, and a projection M on the back ofthe clapper block which will make contact with the face l3, when theblock is in operating posiion.

The abutment at Ta8a is perpendicular to the abutment at l0ll, and theabutment at I3I4 is parallel to abutment lIJ-II but facing in thedirection of abutment 18. The location of the pivot for the clapper boxwith reference to the abutment I 3l4 is such that when the clapper blockswings, this abutment will clear and not resist the swinging movement.

With the construction shown the block will not be forced up against itspivot by pressure against the tool carried by the block because of theabutment la-8a.

The resultant of the upward and backward forces set up by drawing thework along the cutting tool held on the clapper block, when thisresultant force passes above a point slightly forward of midway of theabutment faces 'la-8a., will be taken up by abutments 1-8, 'la-8a, and|3-l4. When the resultant iorce passes below that point, then the loadwill be taken by abutments 1-43, '|a8a, and I 0I|. Accordingly,

the pin that supports the block is not subjected to the pressures inquestion, whether the tool is long or short. There is no resultantwedging action which tends to force the supporting pin downwardly orupwardly or forwardly or backwardly.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A clapper box and block for planers and the like comprising a box, ablock pivoted thereon, means at the lower end of the block and box tointerengage at right angles to a tool ohth'e break when the block is inoperating position on the box, to take upward thrust, and -.m'eans"- onthe upper end of the block and box, abutting each other on a planeparallel with -the toolon the block, to take thrust outwardly on theupper end of the block.

2. A clapper box and block for planers and the like comprising a box,ablock pivoted thereon, means at the lower end of the block and box tointerengage at right angles'to a tool on'the block when the block is inoperating position on the box, to take upward thrust, and-mean's on theupper end of the block and box, abutting'each other on a plane parallelwith the tool on the block/to take thrust outwardly 'on the upper end ofthe block, said block and box having abutting faces-near the upper endof the block at a position below a horizontal plane through the pivotfor the block, said abutment also being parallel to the tool butengaging at 180 degrees from the upper abutment first noted.

ment upwardly and inwardly, said clapper box having in addition anabutment face in back of the clapper block below said pin, and saidclapper block being provided with an abutment face *to engage the-same,said last named abutment being substantially parallel with said abutmentabove said .pin.

JOHN M. WALTER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,467,182 McCann Sept. 4, 19231,637,785 Randolph'et'al. Aug. 2, 1927 1,739,501 Cardullo et a1 Dec. 17,1929 FOREIGN PATENTS Number Country Date 2,089 Great Britain Jan. 26,1897

